1. Technical Field
The present invention relates to a board connecting terminal which is attached together with a circuit board and a holding structure of a circuit board.
2. Background Art
Usually, a structure is proposed that uses a spring structure in an end part of a connector pin and holds a pad on a circuit board by the spring structure to connect a connector terminal to a circuit on the circuit board (for instance, see JP-A-7-201384). In a connecting structure of the connector pin and the circuit board, as shown in FIG. 9 and FIG. 10, the connector pin 1 including a clip main body 5 having a pair of clip parts 3 and 4 which form a holding clearance between them and a lead part 6 extended to a rear surface side of the clip main body 5 is pressed-in to an edge part of the circuit board 9 to connect at least one clip part 3 to a connecting terminal 10 of the circuit board 9.
In the connecting structure of the connector pin and the circuit board, in the clip part 3 connected to the connecting terminal 10, an engaging protruding part 7 is formed which protrudes toward an inner part of the holding clearance. Further, on the surface of the connecting terminal 10 of the circuit board 9, an insulating layer 2 is formed so that parts corresponding to the forms of the engaging protruding parts 7 in which the insulating layer 2 is not formed are partly located and the parts in which the insulating layer 2 is not formed are set as engaging recessed parts 50. Then, the engaging protruding parts 7 are engaged with the engaging recessed parts 50 so that their ends are connected to the surfaces of the connecting terminals 10.
Therefore, according to the above-described connecting structure of the connector pin and the circuit board, if the clip main body 5 of the connector pin 1 is pressed-in to the circuit board 9, when the engaging protruding part 7 is engaged with the engaging recessed part 50, the connector pin 1 is precisely positioned to the circuit board 9 and the connector pin 1 is electrically conducted to the connecting terminal 10 through the engaging protruding part 7. After that, the above-described engaged state is maintained by a resiliency originally provided in the clip parts 3 and 4. Accordingly, arrangement pitches of the connector pins 1 respectively pressed-in to the plurality of connecting terminals 10 on the circuit board 9 are not disordered after the connector pins are pressed-in thereto. Thus, as long as the above-described engaged state is maintained by the resiliency, the connector pin has an extremely high strength to a force in a slipping-off direction exerted on the connector pin 1.
As compared therewith, when a transverse force is applied to the connector pin 1, especially when the transverse force is applied to the lead part 6 so that a large moment for inclining the clip main body 5 operates, if the engaging recessed part 50 and the engaging protruding part 7 have forms whose cross-sectional forms are rectangular forms or elliptical forms so as not to generate a relative rotation between both the parts, the connector pin 1 is not inclined and is maintained in a normal position. Further, even if the cross-sectional forms of the engaging protruding part 7 and the engaging recessed part 50 are circular, an inclination of the connector pin 1 is suitably prevented by a frictional force generated between both the parts.
As a result, in the connecting structure of the connector pin and the circuit board, the connector pin 1 is precisely positioned to the connecting terminal 10 of the circuit board 9, the arrangement pitches of the connector pins 1 are maintained in a uniform state even by the use for a long time after the press-in thereof and the positions of the connector pins 1 are not respectively disordered. Thus, an imperfect short-circuit is prevented between the adjacent connector pins and a reinforcement by a resin may not need to be carried out. Consequently, the number of work processes can be reduced. Further, a reliability of a connected state of the circuit board 9 and the connector pin 1 is improved, so that the lead part 6 of the connector pin 1 is effectively connected to other circuit board and a productive efficiency is improved.